Generally, an electric motor often has a complicate structure. The electric motor and a connecting arm are separated parts, such that when the electric motor is to be assembled into a gimbal, the assembling process is troublesome and complicate and a large space may be occupied. A restricting mechanism for controlling a rotating range of a rotor is a restricting member disposed externally which occupies space outside the electric motor. Moreover, the connecting arm has a relative large dimension and a relative large weight, causing the electric motor to have a relative large weight. When such an electric motor is applied in a gimbal, it's not beneficial for miniaturization and weight reduction of the gimbal.